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EP1179997B1 - Outil abrasif comportant une zone active et une zone de securite - Google Patents

Outil abrasif comportant une zone active et une zone de securite Download PDF

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Publication number
EP1179997B1
EP1179997B1 EP00921441A EP00921441A EP1179997B1 EP 1179997 B1 EP1179997 B1 EP 1179997B1 EP 00921441 A EP00921441 A EP 00921441A EP 00921441 A EP00921441 A EP 00921441A EP 1179997 B1 EP1179997 B1 EP 1179997B1
Authority
EP
European Patent Office
Prior art keywords
tip
tool
tooth
ultrasonic
smooth
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP00921441A
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German (de)
English (en)
Other versions
EP1179997A4 (fr
EP1179997A1 (fr
Inventor
Stephen K. Harrel
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Individual
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Individual
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Publication date
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Publication of EP1179997A4 publication Critical patent/EP1179997A4/fr
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Publication of EP1179997B1 publication Critical patent/EP1179997B1/fr
Anticipated expiration legal-status Critical
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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C3/00—Dental tools or instruments
    • A61C3/02—Tooth drilling or cutting instruments; Instruments acting like a sandblast machine
    • A61C3/03—Instruments operated by vibration

Definitions

  • the present invention relates in general to tools that are moveable on work surfaces to perform operations thereon, and more particularly to tools of the type having safe areas and active areas to remove rough surface areas and provide a smooth surface.
  • Tools are utilized by many different crafts persons for working on various types of materials to fabricate an object with the desired shape or form. While the majority of tools are utilized by machinists and other crafts persons working in similar trades, various types of tools are also utilized on a daily basis by artists, carpenters, cabinet makers, engineers, physicians, dentists, etc. Depending on the application to which the tool is applied, the particular devices may be moved by hand, rotated, reciprocated or otherwise vibrated to operate upon the surface of the workpiece.
  • ultrasonic scalers In the dental field, doctors routinely utilize ultrasonic scalers to remove brittle calculus, tartar, altered cementum and other accumulated residue from a patient's tooth.
  • the material to be removed is universally rough with multiple jagged and protruding edges.
  • the buildup on the enamel of a tooth is undesirable which, if not removed, can be damaging to the tooth and gingival tissue.
  • the ultrasonic scaler is equipped with a tip which mechanically vibrates at a high frequency. When brought into contact with the hardened residue, the brittle material is fractured and eroded and removed from the tooth. The end of the metal tip of the ultrasonic scaler insert fractures and breaks the brittle buildup with a micro-hammer action.
  • the ultrasonic tip can be coated with diamond particles, such as disclosed in U.S. Patent No. 4,731,019 by Martin .
  • the diamond particles covering the ultrasonic scaler tip function to accelerate the abrasion of the brittle calculus. Indeed, an extreme amount of care must be exercised by the doctor in the utilization of this tool, otherwise, the surface of the tooth will be abraded and damaged. It can be appreciated that the doctor or assistant must be very attentive when utilizing this ultrasonic tool, otherwise, the tooth, bone or other hard surface will be damaged beyond repair.
  • Ultrasonic operated devices utilize tips that are constructed of specified lengths so as to be tuned.
  • a tuned tip provides optimum magnitude vibrations and thus is effective to micro-hammer object surfaces.
  • Standard ultrasonic tips are effective only along about 4-6 mm at the end of the tip to remove accretions on a tooth surface. The other portion of the ultrasonic tip is less effective as an instrument to remove calculus and tartar buildup on tooth surfaces.
  • Diamond whetstones are such type of tools. These tools are fabricated by bonding a diamond abrasive in raised islands on the surface of the tool. The raised islands of diamond particles are effective to erode the surface of the workpiece. Again, the surface of the workpiece continues to be eroded as long as the operator moves the whetstone over the surface of the workpiece.
  • ultrasonic scaler tips that are covered with a diamond abrasive grit currently exist.
  • Abrasive or sharp edges on the surface of a scaler tip have been shown to be an effective means of removing tartar and roughness from the tooth surface.
  • studies have demonstrated that abrasive areas and sharp edges, when vibrated by an ultrasonic scaler and placed directly against the tooth surface, will damage the surfaces of the tooth and root. In other words, not only the calculus, tartar, and other unwanted rough surfaces will be removed as desired, but a significant portion of the tooth surface will also be removed, thus causing permanent damage to the tooth.
  • U.S. Patent No. 4,283,175 discloses a dental scaler having a rigid tip that is ultrasonically vibrated.
  • the tip is elongate and is constructed with one or more working edges that are adapted for scaling teeth.
  • the working edges are curved for minimal damage to the teeth. Between the working edges of the tip there are smooth areas defining safe surfaces to further reduce the likelihood of damage to the tooth.
  • a tool with safe and active areas that overcome the disadvantages attendant with the known prior art tools.
  • a tool for removing rough areas from a workpiece until the workpiece is smooth includes a safe area which, when engaged with the workpiece, does not erode or abrade the surface of the workpiece.
  • the tool also includes an active area formed as a depression in the safe area.
  • the active area has formed therein an abrasive mechanism for abrading rough areas of the workpiece that protrude therein.
  • the active area functions to remove the rough areas of the workpiece, it no longer engages the workpiece surface, whereupon the safe area of the tool comes into contact with the smooth workpiece and further removal of the workpiece material is prevented.
  • a scaling tip is fitted into or attached to various forms of ultrasonic transducers utilized in the removal of calculus and roughness from teeth and other hard tissues.
  • the ultrasonic energy can be transmitted from a generator of ultrasonic energy, such as a magnetostrictive pile or a piezoelectric element, to metal scaler tips of various standard shapes to access different areas of the tooth surface.
  • the metal scaler tips may additionally be smooth or may contain grooves or ridges to channel coolant water to the end of the scaler tip.
  • a scaler tip which can be of various shapes, includes a metal tip having one or more shallow depressions on the portion of the tip that contacts the tooth surface. Within these depressions is an active surface that has formed an abrasive or cutting surface.
  • This active surface may include either a coating of abrasive material such as diamond grit, or a sharpened edge of the metal of the scaler tip.
  • the diamond grit or sharpened edge does not extend above the smooth safe areas of the scaler tip.
  • the scaler tip of the invention is safe for use on the tooth surface and does not excessively erode the tooth surface.
  • the metal portion of the scaler tip that comes in contact with the tooth surface has a smooth surface and rounded edges, in the same manner as most existing scaler tips. Additionally, the smooth surface of the scaler tip will effectively protect the tooth and root surfaces from the abrasive or sharpened edges that are located in the shallow depressions formed in the smooth metal surface. However, rough uneven accretions of tartar or other roughness on the tooth surface will project into the shallow depressions and come in contact with the abrasive or sharp edges in the shallow grooves. The rough uneven material on the tooth will thus be rapidly removed by the abrasive or sharpened edges, thereby leaving a smooth surface. Thereafter, only the smooth, non-abrasive metal surface of the scaler will come in contact with the tooth surface.
  • While the tool constructed according to the invention is described below in connection with an ultrasonic tip utilized in periodontal operations, the principles and concepts can be employed on tools that are applicable for use in many other areas and trades. Also, while the operation of the ultrasonic tool described below is in conjunction with movement by way of ultrasonic vibrations, tools constructed in accordance with the invention can also be moved on the workpiece by other mechanisms, such as rotary, circular, reciprocatory, hand moved, or any other action by which one or the other of the tool or the workpiece is moved with respect to the other. Tools that vibrate at frequencies other than ultrasonic, such as vibrations in the sonic frequency range, can employ the principles and concepts of the invention.
  • FIGURE 1 illustrates a preferred form of an ultrasonic insert 8, comprising a metal scaler tip 12 constructed similar to those that are routinely attached to ultrasonic generators for the purpose of removing roughness from the supra and sub gingival portions of a patient's teeth.
  • Ultrasonic scaler tips 12 are typically constructed of a stainless steel or titanium material.
  • the scaler tip 12 is mounted in a plastic holder 10 that functions as a mount for the scaler tip 12 and the ultrasonic generator or transducer (not shown).
  • the scaler tip 12 is constructed with a smooth metal surface 14 that will not abrade or otherwise damage the surface of the tooth. Within the smooth surface 14 of the metal tip 12 are formed a number of linear depressions or grooves 16.
  • the width and depth of the grooves are a function of the roughness of the surface material to be removed from the workpiece.
  • the depth of each groove can be in the range of about 0.06 - 0.5mm, and the width of each groove can be in the range of about 0.33-1.0mm.
  • the grooves are preferably milled in the hard material of the ultrasonic tip 12, but can be formed by other means.
  • the two elongated edges of each depression 16 are rounded so as to not create a sharp edge of metal that might damage or erode the tooth surface.
  • the edges of each groove 16 are made blunt or rounded by the use of an end mill with rounded shoulders, or by using the well-known technique of electric discharge machining.
  • the grooved depressions 16 are coated with an abrasive material such as diamond grit.
  • an abrasive material such as diamond grit.
  • a medium diamond grit is suitable for removing tartar and calculus from a tooth surface.
  • the diamond grit is bonded in the depressions of the grooves 16 by standard diamond grit bonding techniques. Roughness on the tooth surface, such as tartar or calculus, will enter the depressions and be abraded by the abrasive coating. Once the tartar or calculus is removed, the abrasive coating will not come into contact with the smooth tooth surface, thereby preventing damage, wear, and abrasion of the smooth tooth surface.
  • FIGURE 2 is an enlarged cross-sectional view of the scaler tip 12, taken along line 2-2 of FIGURE 1 .
  • the groove depressions 16 are shown formed between the smooth metal surface portions 14 of the scaler tip 12.
  • the rounded edges 28 of each depression 16 are shown.
  • the edges 28 are rounded to an extent where substantially no abrasion occurs when the edges 28 contact either roughened or smooth surfaces of a tooth.
  • the abrasive coating 24 is bonded on the trough portion of each depression 16. It should be noted that the abrasive coating 24 does not extend to the rounded edges 28 of the depression 16, thereby preventing the abrasive 24 from coming into contact with the tooth surface.
  • the rough accretions are thus rapidly removed.
  • many more abrasive coated depressions 16 than shown can be formed around the ultrasonic scaler tip 12. Because the depth of the depressions 16 is a function of the contour of the tooth, the depressions can be formed around the ultrasonic tip 12 with different depths. Alternatively, for highly contoured tooth surfaces, a different ultrasonic tip can be employed that has depressions with smaller openings in the smooth metal surface.
  • FIGURE 3 illustrates an alternate embodiment of the scaler tip of the invention, with one portion of the scaler tip shown enlarged.
  • the depressions are shown as reference numeral 26, and are located between the smooth outer surfaces 14 of the ultrasonic scaler tip. Located below the rounded edge 28 of each depression 26 is a sharpened metal edge 38.
  • the smooth metal 14 of the scaler tip comes into contact with the tooth surface. Any tooth surface roughness, such as calculus or tartar, will come into contact with the sharpened metal edge 38 and will be rapidly removed.
  • Those skilled in the art may also choose to coat the depressions 26 with an abrasive material to facilitate erosion of rough surfaces that project therein.
  • the sharpened edge 38 can quickly remove tartar projections, and the abrasive coating on the depressions 26 can complete smoothing of the tooth surface.
  • FIGURE 4 shows a scaler tip 13 constructed according to another embodiment of the invention.
  • Multiple small depressions 22 are formed in the smooth metal surface of the scaler tip 13. The edges of the small depressions are again made smooth so as not to damage the tooth surface.
  • An abrasive coating lines the depressions and functions in the same manner as described in FIGURE 1 above.
  • the depressions 22 are also formed and coated with an abrasive in the same manner as described above.
  • FIGURES 5 and 6 show yet another embodiment of the invention providing an ultrasonic scaler tip 44 formed as a tubular member 46.
  • One or more windows 48 are cut into the tubular portion 46 of the scaler tip 44.
  • the outside edge 50 of the window 48 that contacts the tooth surface is smooth and rounded so as to not cause damage or abrasion to the tooth surface.
  • the inside edge 52 of the window 48 is sharpened in such a manner as to act on any roughness such as calculus or tartar that projects into the window 48 of the scaler tip 46.
  • the tubular member 46 is constructed of a rigid material, such as stainless steel or titanium, and has an outside diameter in the range of about 1-2 mm, and a sidewall thickness in the range of about 0.10-0.25 mm.
  • the window 48 can have an arcuate opening in the sidewall the size of about 6-10 degrees, or other suitable size to accommodate the surface roughness and contour of the workpiece.
  • the arcuate opening of the window 48 has a size that is also a function of the curvature of the workpiece.
  • the tubular member 46 can have different size windows 48 formed therearound to accommodate different workpiece surface shapes.
  • the smooth surfaces of the scaler tip that are not effective to substantially abrade the tooth are considered as "safe” areas, whereas the abrasive-coated areas and the sharp abrading edges are considered as “active” areas.
  • the tool can be vibrated in both the subsonic and ultrasonic frequency ranges.
  • a diamond grit abrasive is utilized in the preferred form of the invention, other grits, such as corundum and others can be utilized with suitable effectiveness.

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  • Health & Medical Sciences (AREA)
  • Oral & Maxillofacial Surgery (AREA)
  • Dentistry (AREA)
  • Epidemiology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Dental Tools And Instruments Or Auxiliary Dental Instruments (AREA)

Claims (6)

  1. Outil destiné à éliminer des accrétions d'une surface de dent, ledit outil comportant une pointe allongée (12, 13, 44) formée en un métal rigide et présentant une taille appropriée à des vibrations ultrasoniques, ladite pointe (12, 13, 44) présentant une surface sensiblement lisse (14, 15, 50) qui ne risque pas d'endommager la surface de dent, caractérisé en ce que :
    ladite pointe comporte au moins une cavité (16, 22, 26) sur ladite surface lisse (14, 15, 50) ; et
    un mécanisme abrasif (24, 38, 52) situé dans ladite cavité (16, 22, 26) et sensible aux vibrations ultrasoniques afin d'éliminer des accrétions qui font saillie dans ladite cavité (16, 22, 26).
  2. Outil selon la revendication 1, dans lequel ladite pointe (12, 13) comporte un mécanisme abrasif qui comprend des particules abrasives (24) collées sur une surface de ladite cavité (16).
  3. Outil selon la revendication 1, dans lequel ladite pointe (12, 44) comporte un mécanisme abrasif comprenant un bord effilé (38, 52) formé dans ladite cavité (26).
  4. Outil selon la revendication 1, dans lequel chaque cavité (16) de ladite pointe (12) comprend une ou plusieurs rainures allongées (16).
  5. Outil selon la revendication 1, dans lequel ladite pointe (12, 13) comporte une ou plusieurs rainures (16, 22) formées axialement sur la surface lisse (14, 15).
  6. Outil selon la revendication 1, dans lequel ladite cavité comporte une rainure (16, 22, 26) avec un bord (28), où ladite rainure (16, 22, 26) rejoint ladite surface lisse (14, 15), ledit bord (28) est arrondi et ne comporte pas ledit mécanisme abrasif (24, 38).
EP00921441A 1999-03-26 2000-03-23 Outil abrasif comportant une zone active et une zone de securite Expired - Lifetime EP1179997B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US12647499P 1999-03-26 1999-03-26
US126474P 1999-03-26
PCT/US2000/007858 WO2000057806A1 (fr) 1999-03-26 2000-03-23 Outil abrasif comportant une zone active et une zone de sécurité

Publications (3)

Publication Number Publication Date
EP1179997A1 EP1179997A1 (fr) 2002-02-20
EP1179997A4 EP1179997A4 (fr) 2004-09-15
EP1179997B1 true EP1179997B1 (fr) 2008-05-21

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ID=22425027

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00921441A Expired - Lifetime EP1179997B1 (fr) 1999-03-26 2000-03-23 Outil abrasif comportant une zone active et une zone de securite

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EP (1) EP1179997B1 (fr)
AU (1) AU4176400A (fr)
DE (1) DE60038964D1 (fr)
WO (1) WO2000057806A1 (fr)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6910889B1 (en) 2000-11-02 2005-06-28 San Diego Swiss Machining, Inc. Ultrasonic surgical dental tool having a rasp tip
FR2876574B1 (fr) * 2004-10-20 2007-11-02 Patrick Lesage Insert de taille pour appareil dentaire a vibrations
US9788925B2 (en) 2009-08-19 2017-10-17 Vicky L Moran Transducer activated tool with water conduit

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2694885A (en) * 1952-04-22 1954-11-23 Micromatic Honc Corp Honing tool with stones disposed at an angle to the tool axis
US2797535A (en) * 1954-02-08 1957-07-02 Mid West Abrasive Co Honing head with oblique abrasive elements and method of making the same
US4283175A (en) * 1979-11-05 1981-08-11 Syntex (U.S.A.) Inc. Dental scaler having scaling tip with rounded edge work surfaces particularly suitable for circular or ellipsoidal patterns of vibration
US4353696A (en) * 1981-07-10 1982-10-12 Bridges Byron K Vibrating dental tool device and method
DE3346189C1 (de) * 1983-12-21 1985-06-13 Carl Hurth Maschinen- und Zahnradfabrik GmbH & Co, 8000 München Abrichtwerkzeug zum Abrichten von abrasiven zahnradartigen Feinbearbeitungswerkzeugen
US4731019A (en) * 1984-06-04 1988-03-15 Howard Martin Diamond coated scaler dental instrument for ultrasonic operation
US6015420A (en) * 1997-03-06 2000-01-18 Scimed Life Systems, Inc. Atherectomy device for reducing damage to vessels and/or in-vivo stents

Also Published As

Publication number Publication date
DE60038964D1 (de) 2008-07-03
AU4176400A (en) 2000-10-16
WO2000057806A1 (fr) 2000-10-05
EP1179997A4 (fr) 2004-09-15
EP1179997A1 (fr) 2002-02-20

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